Extremely Rare Brown & Sharpe Draftsman's Protractor- Pat. Dec., 2, 1890

US $33

Mars, Pennsylvania, United States
May 26th

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This auction is for a Brown & Sharpe Draftsman's Protractor- Pat. Dec 2, 1890 engraved on the front. This is the information I have been able to find on it. This one in my photo is almost identical to the one in the Smithsonian, National Museum of American History, except it has 11 holes on the top. Not sure if this was an earlier design or later. Pretty cool usable piece of History. In usable vintage condition. It could use a good cleaning. I don't think its rust, I think it is ink.(I don't want to touch it) It has a name engraved on it. The original case is still intact but the top on the lid is falling apart and just holding on. (in vintage condition.) It measures 10 1/4" long x 6 1/8" tall in the position as in the photos. The inventor was Samuel Darling. The maker is Darling, Brown & Sharpe. The inside of the case is a purple velvet. The outside of the case is Morocco leather. And the protractor is made from Sheet Steel. It was made in The United Sates in Providence, Rhode Island. The date made 1889-1892. It says the patent date was 1887. MEASUREMENTS: overall: 2 cm x 27.2 cm x 17 cm; 25/32 in x 10 23/32 in x 6 11/16 in DESCRIPTION: In the late 19th century, American draftsmen experimented with different designs for making protractors more versatile. For instance, the secretive machinist Samuel Darling, who operated a separate partnership with Joseph R. Brown and Lucian Sharpe of Providence, R.I., between 1866 and 1892, patented a "bevel and protractor" on July 19, 1887. This was a nearly circular protractor with an extended arm that slid along and rotated around a ruler. Alton J. Shaw, who apprenticed in the main firm of Brown & Sharpe, came up with a design that was less cumbersome than Darling's. Although Shaw filed for a patent one month before Darling did, Shaw's patent was not granted until August 2, 1887. His protractor consisted of a circle with an extending arm, cut from sheet steel, which fit on a groove within a three-sided square, also cut from sheet steel. An advantage of this protractor was its reversibility. Shaw assigned his patent to Darling, Brown, & Sharpe on August 19 in exchange for $75. The firm marketed the protractor for $6.50, or for $7.75 with a case. In its catalogs, Brown & Sharpe adopted the British spelling, "draughtsmen's". This instrument is an example of Shaw's design. The protractor is divided by single degrees and marked by fives from 0 to 90 in the clockwise direction. Thirty more unnumbered divisions extend past the 90° mark. A vernier on the frame allows angles to be measured to one minute of arc. The interior of the protractoris marked: Darling, Brown & Sharpe. (/) Providence. R.I. (/) Pat. Aug. 2. 1887. The protractor is in a wood and morocco leather case that is lined with purple velvet. The case has broken apart into at least three pieces. A worn instruction sheet (ID number MA*336072.1.1), dated August 1889, is stored with the object. The instructions indicate that a guiding lever, which was placed in two of the eleven holes at the top of the protracting circle, is missing from the object. Shaw later moved to Milwaukee, Wis., and then to Muskegon, Mich., where he established the Shaw Electric Crane Company. The company became Lift-Tech International in 1986. The Brown & Sharpe Mfg. Co. absorbed Darling, Brown & Sharpe in 1892. After over a century as one of the largest American machining firms, Brown & Sharpe ceased manufacturing machine tools and drawing instruments in 1991. The firm now manufactures optical measuring instruments as a subsidiary of Hexagon Metrology. This protractor was owned by the renowned American designer of steam engines, Erasmus Darwin Leavitt Jr. (1836–1916), and donated by his granddaughter, Margaret van D. Rice. See also ID number 1990.0317.02. References: Oscar James Beale, Practical Treatise on Gearing (Providence, R.I.: Brown & Sharpe Mfg. Co., 1886), 73-75; Samuel Darling, "Bevel andProtractor" (U.S. Patent 366,651 issued July 19, 1887); Alton J. Shaw, "Protractor" (U.S. Patent 367,673 issued August 2, 1887); Amy Ackerberg-Hastings, "The Brown & Sharpe Draftsmen's Protractor," Rittenhouse 15, no. 1 (2001): 31–38; Henry Dexter Sharpe, A Measure of Perfection: The History of Brown & Sharpe (North Kingston, R.I.: Brown & Sharpe, 1949), CATALOG NUMBER: 336072 SEE MORE ITEMS IN: Medicine and Science: Mathematics Protractors DATA SOURCE: National Museum of American History, Kenneth E. Behring Center